Space vector modulation, motor control, implementation question

[david316]

Hello,

I am after some help to try and understand SVM implementation is a micro that controls a motor.

As I understand it one of the advantages of using space vector modulation over sinusoidal PWM modulation in motor control is that it can control the phase voltages such that the line-to-line voltages are maximised. There are different implementation of space vector implementation as described here (https://microchipdeveloper.com/mct5001:zsm-viewer). It appears the mid-point clamp is the most popular SVM. In this method the "zero-sequence" component is a triangular wave which when added to a sine wave allows maximum line-to-line voltage.

In a typically implementation of a mid-point clamp SVM is the design such that for required "modulation indexes" below 0.866 (i.e. sinusoidal modulation is adequate) the SVM implementation results in sin waves on the phase voltages, whereas for "modulation indexes" above 0.866 the triangular zero-sequence waveform gets added to the sine waves to allow for greater line-to-line voltages?

Thanks for any help.

 

[essenmein]

Don't know about mid point clamp being the most popular, I've only ever seen the third harmonic line to neutral waveform, where the third harmonic is canceled line to line. This third harmonic was always present, regardless of modulation index.

 

[david316]

Thanks.